1// String based streams -*- C++ -*-
2
3// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
4// Free Software Foundation, Inc.
5//
6// This file is part of the GNU ISO C++ Library.  This library is free
7// software; you can redistribute it and/or modify it under the
8// terms of the GNU General Public License as published by the
9// Free Software Foundation; either version 2, or (at your option)
10// any later version.
11
12// This library is distributed in the hope that it will be useful,
13// but WITHOUT ANY WARRANTY; without even the implied warranty of
14// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15// GNU General Public License for more details.
16
17// You should have received a copy of the GNU General Public License along
18// with this library; see the file COPYING.  If not, write to the Free
19// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
20// USA.
21
22// As a special exception, you may use this file as part of a free software
23// library without restriction.  Specifically, if other files instantiate
24// templates or use macros or inline functions from this file, or you compile
25// this file and link it with other files to produce an executable, this
26// file does not by itself cause the resulting executable to be covered by
27// the GNU General Public License.  This exception does not however
28// invalidate any other reasons why the executable file might be covered by
29// the GNU General Public License.
30
31/** @file sstream.tcc
32 *  This is an internal header file, included by other library headers.
33 *  You should not attempt to use it directly.
34 */
35
36//
37// ISO C++ 14882: 27.7  String-based streams
38//
39
40#ifndef _SSTREAM_TCC
41#define _SSTREAM_TCC 1
42
43#pragma GCC system_header
44
45#include <sstream>
46
47_GLIBCXX_BEGIN_NAMESPACE(std)
48
49  template <class _CharT, class _Traits, class _Alloc>
50    typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
51    basic_stringbuf<_CharT, _Traits, _Alloc>::
52    pbackfail(int_type __c)
53    {
54      int_type __ret = traits_type::eof();
55      if (this->eback() < this->gptr())
56	{
57	  // Try to put back __c into input sequence in one of three ways.
58	  // Order these tests done in is unspecified by the standard.
59	  const bool __testeof = traits_type::eq_int_type(__c, __ret);
60	  if (!__testeof)
61	    {
62	      const bool __testeq = traits_type::eq(traits_type::
63						    to_char_type(__c),
64						    this->gptr()[-1]);	  
65	      const bool __testout = this->_M_mode & ios_base::out;
66	      if (__testeq || __testout)
67		{
68		  this->gbump(-1);
69		  if (!__testeq)
70		    *this->gptr() = traits_type::to_char_type(__c);
71		  __ret = __c;
72		}
73	    }
74	  else
75	    {
76	      this->gbump(-1);
77	      __ret = traits_type::not_eof(__c);
78	    }
79	}
80      return __ret;
81    }
82
83  template <class _CharT, class _Traits, class _Alloc>
84    typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
85    basic_stringbuf<_CharT, _Traits, _Alloc>::
86    overflow(int_type __c)
87    {
88      const bool __testout = this->_M_mode & ios_base::out;
89      if (__builtin_expect(!__testout, false))
90	return traits_type::eof();
91
92      const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
93      if (__builtin_expect(__testeof, false))
94	return traits_type::not_eof(__c);
95
96      const __size_type __capacity = _M_string.capacity();
97      const __size_type __max_size = _M_string.max_size();
98      const bool __testput = this->pptr() < this->epptr();
99      if (__builtin_expect(!__testput && __capacity == __max_size, false))
100	return traits_type::eof();
101
102      // Try to append __c into output sequence in one of two ways.
103      // Order these tests done in is unspecified by the standard.
104      const char_type __conv = traits_type::to_char_type(__c);
105      if (!__testput)
106	{
107	  // NB: Start ostringstream buffers at 512 chars.  This is an
108	  // experimental value (pronounced "arbitrary" in some of the
109	  // hipper english-speaking countries), and can be changed to
110	  // suit particular needs.
111	  //
112	  // _GLIBCXX_RESOLVE_LIB_DEFECTS
113	  // 169. Bad efficiency of overflow() mandated
114	  // 432. stringbuf::overflow() makes only one write position
115	  //      available
116	  const __size_type __opt_len = std::max(__size_type(2 * __capacity),
117						 __size_type(512));
118	  const __size_type __len = std::min(__opt_len, __max_size);
119	  __string_type __tmp;
120	  __tmp.reserve(__len);
121	  if (this->pbase())
122	    __tmp.assign(this->pbase(), this->epptr() - this->pbase());
123	  __tmp.push_back(__conv);
124	  _M_string.swap(__tmp);
125	  _M_sync(const_cast<char_type*>(_M_string.data()),
126		  this->gptr() - this->eback(), this->pptr() - this->pbase());
127	}
128      else
129	*this->pptr() = __conv;
130      this->pbump(1);
131      return __c;
132    }
133
134  template <class _CharT, class _Traits, class _Alloc>
135    typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
136    basic_stringbuf<_CharT, _Traits, _Alloc>::
137    underflow()
138    {
139      int_type __ret = traits_type::eof();
140      const bool __testin = this->_M_mode & ios_base::in;
141      if (__testin)
142	{
143	  // Update egptr() to match the actual string end.
144	  _M_update_egptr();
145
146	  if (this->gptr() < this->egptr())
147	    __ret = traits_type::to_int_type(*this->gptr());
148	}
149      return __ret;
150    }
151
152  template <class _CharT, class _Traits, class _Alloc>
153    typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
154    basic_stringbuf<_CharT, _Traits, _Alloc>::
155    seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
156    {
157      pos_type __ret =  pos_type(off_type(-1));
158      bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
159      bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
160      const bool __testboth = __testin && __testout && __way != ios_base::cur;
161      __testin &= !(__mode & ios_base::out);
162      __testout &= !(__mode & ios_base::in);
163
164      // _GLIBCXX_RESOLVE_LIB_DEFECTS
165      // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
166      const char_type* __beg = __testin ? this->eback() : this->pbase();
167      if ((__beg || !__off) && (__testin || __testout || __testboth))
168	{
169	  _M_update_egptr();
170
171	  off_type __newoffi = __off;
172	  off_type __newoffo = __newoffi;
173	  if (__way == ios_base::cur)
174	    {
175	      __newoffi += this->gptr() - __beg;
176	      __newoffo += this->pptr() - __beg;
177	    }
178	  else if (__way == ios_base::end)
179	    __newoffo = __newoffi += this->egptr() - __beg;
180
181	  if ((__testin || __testboth)
182	      && __newoffi >= 0
183	      && this->egptr() - __beg >= __newoffi)
184	    {
185	      this->gbump((__beg + __newoffi) - this->gptr());
186	      __ret = pos_type(__newoffi);
187	    }
188	  if ((__testout || __testboth)
189	      && __newoffo >= 0
190	      && this->egptr() - __beg >= __newoffo)
191	    {
192	      this->pbump((__beg + __newoffo) - this->pptr());
193	      __ret = pos_type(__newoffo);
194	    }
195	}
196      return __ret;
197    }
198
199  template <class _CharT, class _Traits, class _Alloc>
200    typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
201    basic_stringbuf<_CharT, _Traits, _Alloc>::
202    seekpos(pos_type __sp, ios_base::openmode __mode)
203    {
204      pos_type __ret =  pos_type(off_type(-1));
205      const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
206      const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
207
208      const char_type* __beg = __testin ? this->eback() : this->pbase();
209      if ((__beg || !off_type(__sp)) && (__testin || __testout))
210	{
211	  _M_update_egptr();
212
213	  const off_type __pos(__sp);
214	  const bool __testpos = (0 <= __pos
215				  && __pos <= this->egptr() - __beg);
216	  if (__testpos)
217	    {
218	      if (__testin)
219		this->gbump((__beg + __pos) - this->gptr());
220	      if (__testout)
221                this->pbump((__beg + __pos) - this->pptr());
222	      __ret = __sp;
223	    }
224	}
225      return __ret;
226    }
227
228  template <class _CharT, class _Traits, class _Alloc>
229    void
230    basic_stringbuf<_CharT, _Traits, _Alloc>::
231    _M_sync(char_type* __base, __size_type __i, __size_type __o)
232    {
233      const bool __testin = _M_mode & ios_base::in;
234      const bool __testout = _M_mode & ios_base::out;
235      char_type* __endg = __base + _M_string.size();
236      char_type* __endp = __base + _M_string.capacity();
237
238      if (__base != _M_string.data())
239	{
240	  // setbuf: __i == size of buffer area (_M_string.size() == 0).
241	  __endg += __i;
242	  __i = 0;
243	  __endp = __endg;
244	}
245
246      if (__testin)
247	this->setg(__base, __base + __i, __endg);
248      if (__testout)
249	{
250	  this->setp(__base, __endp);
251	  this->pbump(__o);
252	  // egptr() always tracks the string end.  When !__testin,
253	  // for the correct functioning of the streambuf inlines
254	  // the other get area pointers are identical.
255	  if (!__testin)
256	    this->setg(__endg, __endg, __endg);
257	}
258    }
259
260  // Inhibit implicit instantiations for required instantiations,
261  // which are defined via explicit instantiations elsewhere.
262  // NB:  This syntax is a GNU extension.
263#if _GLIBCXX_EXTERN_TEMPLATE
264  extern template class basic_stringbuf<char>;
265  extern template class basic_istringstream<char>;
266  extern template class basic_ostringstream<char>;
267  extern template class basic_stringstream<char>;
268
269#ifdef _GLIBCXX_USE_WCHAR_T
270  extern template class basic_stringbuf<wchar_t>;
271  extern template class basic_istringstream<wchar_t>;
272  extern template class basic_ostringstream<wchar_t>;
273  extern template class basic_stringstream<wchar_t>;
274#endif
275#endif
276
277_GLIBCXX_END_NAMESPACE
278
279#endif
280